1. Field of the Invention
The invention relates to a crankcase ventilation valve for an internal combustion engine, with a valve housing, a gas inflow duct connected to the interior of the crankcase, a gas outflow duct connected to an air intake duct of the internal combustion engine, and a diaphragm which divides the valve housing into a crankcase-side inner chamber and an outer chamber and which has a ventilation valve disk diaphragm, together with the ventilation valve disk, selectively open or close the gas outflow duct, depending on the pressure difference between the two chambers,
2. Discussion of the Prior Art
A crankcase ventilation known, for example, from DE 44 06 986 A1, EP 0 459 031 B1, DE 27 53 335 C2 and EP 0 730 086 A1 is a closed system for the recirculation of pollutants, such as, for example, oil vapor and unburnt hydrocarbons, which pass along the pistons into the crankcase interior, out of the crankcase to the engine combustion system, so that these pollutants do not escape into the environment. In this case, an intake duct of the internal combustion engine is connected to an outlet of the crankcase ventilation. Since a greater or lesser vacuum prevails in this intake duct, depending on the operating state of the internal combustion engine, precautions must be taken to ensure that this vacuum is not propagated to too great an extent into the crankcase, since air would otherwise be sucked into the crankcase from outside in an undesirable way, for example via a crankshaft seal.
For this purpose, DE 44 06 986 A1 proposes a generic crankcase ventilation valve. Here, a bore is provided in the cover of the valve housing, said bore connecting the outer chamber on a diaphragm side facing away from the crankcase to the ambient pressure. The disadvantage of this, however, is that the gas outflow duct is arranged on the crankcase side in relation to the chamber at ambient pressure and it is therefore necessary to have a complicated routing of the gas duct out of the ventilation valve through the crankcase to the air intake duct of the internal combustion engine. A modification may therefore be necessary if the internal combustion engine has different installation positions with different paths from the ventilation valve to the air intake duct of the internal combustion engine.